The present disclosure relates generally to an apparatus for selectively distributing a laser beam from a single laser source to one of a plurality of outputs. More specifically, the present disclosure relates to a sealed apparatus through which laser energy from a single source is directed in a manner that selectively distributes the laser energy to one of a plurality of outputs while protecting the distribution elements contained therein from contamination.
Laser technology has developed greatly over the past few decades in a manner that finds lasers being used in a multitude of environments to accomplish a great number of tasks. Some well-known processes for which lasers are being employed include telecommunications, machining of tools and parts and medical procedures. Further, the number of applications in which lasers are employed continues to increase as the power level of the available lasers increases. As the power level of the energy being transmitted along the fiber increases, such as laser energy employed in medical treatment and diagnosis, the need for precise, the need to provide low loss coupling greatly increases. Further, such couplers must often aggregate energy from multiple conduits into a single transmission fiber or distribute the energy from a single laser source to one or a plurality of outputs.
There are now a number of high-power single-mode fiber lasers having output power in the range of 1-50 kW that are coming into widespread use in the industrial fields of welding, high-speed cutting, brazing, and drilling. Such fiber lasers have high wall plug power efficiency and very good beam characteristics. The beam from these fiber lasers can be focused to small spot sizes with long focal length lenses with consistent beam properties independent of power level or pulse duration. Ytterbium single-mode fiber lasers with an M2 of 1.1 have continually increased in power to the multi-kW level, and can be focused to 10-15 μm spot diameters with perfect Gaussian distribution. Further increasing power will open up additional markets in the future.
One of the difficulties that has arisen is that as the power of the laser energy that must be distributed increases, the difficulty relating to the distribution of that energy also greatly increases. These distribution systems must be robust and capable of handling the waste heat generated through the distribution of the laser energy. Further, the devices must provide a very stable platform onto which all of the various components are installed to insure correct alignment of the various input and output ports to prevent losses resulting from poorly aligned components.
In the prior art, such distribution systems are typically built on a large and heavy slab of metal that serves as a base platform to which the other components are mounted. In addition to the various switching mirrors used to distribute the laser energy, motors for moving the mirrors, electrical wiring and coolant conduits are all installed on the platform. Once assembled, a cover is then placed over the top of the platform to protect all of the elements contained thereon. This arrangement, however, creates problems of its own in that all of the components are contained within the same cavity through which the laser energy is distributed. The heat generated by the laser energy is transferred into the various other components contained within the beam cavity. As the wires, pipes and motor windings are heated, they off gas coating all of the components within the beam cavity including the switching mirrors and optics with a film that obscures these optical elements resulting is energy loss during distribution operations. In addition, operation of the motors causes dust to be emitted that can also settle onto the optical elements. Further, should any component within the beam cavity fail or require servicing, the entire device must be shut down so that the cover can be removed to allow access to the components contained therein.
Therefore, there is a need for an apparatus that can selectively distribute a laser beam from a single laser source to one of a plurality of outputs.
There is a further need for a reduced size, sealed apparatus through which laser energy from a single source is directed in a manner that selectively distributes the laser energy to one of a plurality of outputs while protecting the distribution elements contained therein from contamination.
Still further there is a need for an apparatus for distributing laser energy that is compact and modular in nature while providing a sealed beam cavity that protects the optics contained therein from the contamination issues encountered in the prior art.
Yet there is a further need for an apparatus for distributing laser energy configured with reflective components witch are contained within the housing of apparatus, whereas the remainder of the apparatus is outside of the housing yet supported in a manner that allows 360° of rotational adjustment to facilitate carefully alignment of the reflective components.